Touch screen panel

ABSTRACT

A touch screen panel is provided. The touch screen panel includes an Indium Tin Oxide (ITO) sensor glass layer, a window glass layer mounted above the ITO sensor glass layer by means of an Optical Clear Adhesive (OCA), a conductive layer disposed between a surface of the window glass layer and a surface of the ITO sensor glass layer that includes an electrode pattern, and a touch screen control unit mounted on one of the window glass layer surface and the ITO sensor glass layer surface on which the conductive layer is mounted.

PRIORITY

This application claims the benefit under 35 U.S.C. §119(a) of a Koreanpatent application filed in the Korean Intellectual Property Office onMar. 31, 2010 and assigned Serial No. 10-2010-0029017, the entiredisclosure of which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a touch screen panel used as a datainput/output means of an electrical device. More particularly, thepresent invention relates to a touch screen panel in which a controlunit for touch screen control is directly mounted on a sensor surface toimprove touch sensitivity as well as preventing a touch fault.

2. Description of the Related Art

A variety of electronic devices employ an input unit for data input andan output unit for data output. A key button unit or the like is arepresentative example of the input unit. A display unit including aLiquid Crystal Display (LCD) module is a representative example of theoutput unit.

A touch screen panel capable of performing data input/output at the sameposition has recently been launched to diversify a function of theelectronic device while significantly reducing a volume of theelectronic device. The touch screen panel has a transparent touch paneldisposed above the LCD module to simultaneously perform data input andoutput. There are various types of touch panels, such as a resistivetouch panel, a capacitive touch panel, an ultrasonic wave touch typepanel, an optical (infrared) sensor type touch panel, an electromagneticinduction type touch panel, etc.

Among the aforementioned touch panels, the capacitive touch panelincludes a window portion made of a dielectric material, a dielectriclayer (e.g., an Indium Tin Oxide (ITO) film layer and an ITO glasslayer) bonded below the window portion and made of a PolyethyleneTerephthalate (PET) or glass material, a conductive material coatinglayer which is disposed above the dielectric layer and of which aportion for touch sensing is coated with a transparent conductivematerial such as ITO, and an Optical Clear Adhesive (OCA) for bondingthe ITO layer and the window portion. The conductive material coatinglayer includes a silver paste electrode portion. A Flexible PrintedCircuit (FPC) is electrically connected to the electrode portion. Acontrol unit for touch screen control is mounted on the FPC. An endportion of the FPC on which the control unit is mounted iselectronically connected to a main board of the device.

However, when the control unit for touch sensing is mounted on the FPCas described above, the control unit may experience a contact fault dueto flexibility of the FPC. As a result, touch sensitivity deteriorates,which leads to deterioration in reliability of the device.

SUMMARY OF THE INVENTION

An aspect of the present invention is to address at least theabove-mentioned problems and/or disadvantages and to provide at leastthe advantages described below. Accordingly, an aspect of the presentinvention is to provide a touch screen panel implemented to improvetouch sensitivity by mounting a control unit on a relatively solidportion of the touch screen panel without additional expansion space.

Another aspect of the present invention is to provide a touch screenpanel implemented to prevent a contact failure of a control unit bymounting the control unit on an Indium Tin Oxide (ITO) glass layer or awindow glass layer which is a relatively solid component of the touchscreen panel and thereby to improve reliability of a device.

In accordance with an aspect of the present invention, a touch screenpanel is provided. The touch screen panel includes an ITO sensor glasslayer, a window glass layer mounted above the ITO sensor glass layer bymeans of an Optical Clear Adhesive (OCA), a conductive layer disposedbetween a surface of the window glass layer and a surface of the ITOsensor glass layer that includes an electrode pattern, and a touchscreen control unit mounted on one of the window glass layer surface andthe ITO sensor glass layer surface on which the conductive layer ismounted.

In accordance with another aspect of the present invention, a touchscreen panel is provided. The touch screen panel includes a window glasslayer, a conductive layer mounted on a lower surface of the window glasslayer that includes an electrode pattern, and a touch screen controlunit mounted on the lower surface of the window glass layer.

Other aspects, advantages, and salient features of the invention willbecome apparent to those skilled in the art from the following detaileddescription, which, taken in conjunction with the annexed drawings,discloses exemplary embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certainexemplary embodiments of the present invention will be more apparentfrom the following description taken in conjunction with theaccompanying drawings, in which:

FIG. 1 is a perspective view of a portable terminal that employs a touchscreen panel according to an exemplary embodiment of the presentinvention;

FIG. 2 is an exploded perspective view of the display unit of FIG. 1according to an exemplary embodiment of the present invention;

FIG. 3 is a cross-sectional view illustrating a structure of a touchscreen panel according to an exemplary embodiment of the presentinvention;

FIG. 4 is a cross-sectional view illustrating a structure of a touchscreen panel according to another exemplary embodiment of the presentinvention; and

FIG. 5 is a cross-sectional view illustrating a structure of a touchscreen panel according to still another exemplary embodiment of thepresent invention.

Throughout the drawings, it should be noted that like reference numbersare used to depict the same or similar elements, features, andstructures.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The following description with reference to the accompanying drawings isprovided to assist in a comprehensive understanding of exemplaryembodiments of the invention as defined by the claims and theirequivalents. It includes various specific details to assist in thatunderstanding but these are to be regarded as merely exemplary.Accordingly, those of ordinary skill in the art will recognize thatvarious changes and modifications of the embodiments described hereincan be made without departing from the scope and spirit of theinvention. In addition, descriptions of well-known functions andconstructions are omitted for clarity and conciseness.

The terms and words used in the following description and claims are notlimited to the bibliographical meanings, but, are merely used by theinventor to enable a clear and consistent understanding of theinvention. Accordingly, it should be apparent to those skilled in theart that the following description of exemplary embodiments of thepresent invention are provided for illustration purpose only and not forthe purpose of limiting the invention as defined by the appended claimsand their equivalents.

It is to be understood that the singular forms “a,” “an,” and “the”include plural referents unless the context clearly dictates otherwise.Thus, for example, reference to “a component surface” includes referenceto one or more of such surfaces.

By the term “substantially” it is meant that the recited characteristic,parameter, or value need not be achieved exactly, but that deviations orvariations, including for example, tolerances, measurement error,measurement accuracy limitations and other factors known to those ofskill in the art, may occur in amounts that do not preclude the effectthe characteristic was intended to provide.

Although a portable terminal and a touch screen panel applied to theportable terminal are illustrated in the drawings, the present inventionis not limited thereto. For example, the present invention can alsoapply to various types of electronic devices including the touch screenpanel.

FIG. 1 is a perspective view of a portable terminal that employs a touchscreen panel according to an exemplary embodiment of the presentinvention.

Referring to FIG. 1, a terminal 100 has a display unit 1 on a frontsurface 101 of the terminal 100. The display unit 1 supports datainput/output functions simultaneously. A speaker 102 is disposed on afront surface 101 of the terminal 100 above the display unit 1. Amicrophone 103 is disposed on a front surface 101 of the terminal 100below the display unit 1.

FIG. 2 is an exploded perspective view of the display unit of FIG. 1according to an exemplary embodiment of the present invention.

Referring to FIG. 2, the display unit 1 includes a reinforcement plate70, a backlight unit 60, a double-sided tape 50, a Liquid CrystalDisplay (LCD) panel 40, and touch screen panels 10, 20, and 30, whichare sequentially laminated on the reinforcement plate 70.

The reinforcement plate 70 may be made of a metal material such as SteelUse Stainless (SUS). The reinforcement plate 70 protects not only thebacklight unit 60 but also other elements placed thereon, i.e., the LCDpanel 40 and the touch screen panels 10, 20, and 30, and allows thedisplay unit 1 to be used as one assembly.

A portion of a Flexible Printed Circuit (FPC) 18 protrudes to an outerside of the touch screen panels 10, 20, and 30. A connection member isformed on one end portion of the FPC 18 for electrical connection to acircuit board of a device. However, unlike the related art, a controlunit for touch screen control (hereinafter, simply referred to as acontrol unit) is not connected via the FPC 18. The control unit ofexemplary embodiments of the present invention may be disposed at anIndium Tin Oxide (ITO) glass layer or a window glass layer, i.e., acomponent of the touch panel. Hereinafter, additional details of theexemplary embodiments of the present invention will be described.

FIG. 3 is a cross-sectional view illustrating a structure of a touchscreen panel according to an exemplary embodiment of the presentinvention.

Referring to FIG. 3, a touch screen panel 10 includes an ITO sensorglass layer 11 disposed at a lowermost portion thereof. A conductivelayer 12 is coated on an upper surface of the ITO sensor glass layer 11.The conductive layer 12 is preferably made of a transparent conductivematerial including one of ITO, Indium Zinc Oxide (IZO), etc. Anelectrode pattern is formed on the conductive layer 12, and electricalconnection may be possible through a silver paste electrode portion (notshown) in one or more ends of the conductive layer 12. A window glasslayer 14 is laminated above the conductive layer 12 by using an OpticalClear Adhesive (OCA) 13 to construct the touch screen panel 10.

Although not shown, the conductive layer 12 may alternatively be coatedon a lower surface of the window glass layer 14, which is laminatedabove the ITO sensor glass layer 11 by using the OCA 13.

According to an exemplary embodiment of the present invention, a touchcontrol unit 17 is mounted on one of the surface of ITO sensor glasslayer 11 or the surface of the window glass layer 14 that has theconductive layer 12 coated thereon. More specifically, the control unit17 may be mounted on the surface of the ITO sensor glass layer 11 or thesurface of window glass layer 14 by using Tape Automated Bonding (TAB).Preferably, the control unit 17 may be implemented with a Tape CarrierPackage (TCP) on which a plurality of Integrated Circuits (ICs) ismounted. The TCP may be mounted above the surface of the ITO sensorglass layer 11 or below the surface of the window glass layer 14 in anelectrical bonding manner. In this case, an Anisotropic Conductive Film(ACF) 16 is used as an adhesive member for providing bonding betweenelectrodes of the conductive layer 12.

An FPC 18 which protrudes with a specific length by using the ACF 16 andwhich is used for electrical connection to a circuit board of the devicemay be mounted on the one of the surface of the ITO sensor glass layer11 and the surface of the window glass layer 14 on which the controlunit 17 is mounted. A connection member 181 is formed at one end portionof the FPC 18 to provide electrical connection with the device. Inaddition, an oxidation protection coating layer 15 may be laminated onan exposed upper portion of the conductive layer 12 to protect theconductive layer 12.

While certain elements of touch screen panel 10 have been shown in FIG.3 and described herein, the touch screen panel 10 is not limited theretoand may include other elements that are not shown in FIG. 3 or describedherein for conciseness in explanation.

FIG. 4 is a cross-sectional view illustrating a structure of a touchscreen panel according to another exemplary embodiment of the presentinvention.

Referring to FIG. 4, a touch screen panel 20 includes an ITO sensorglass layer 21 disposed at a lowermost portion thereof. A conductivelayer 22 is coated on an upper surface of the ITO sensor glass layer 21.The conductive layer 22 is preferably made of a transparent conductivematerial including one of ITO, IZO etc. An electrode pattern is formedon the conductive layer 22, and electrical connection may be possiblethrough a silver paste electrode portion (not shown) in one or more endsof the conductive layer 22. A window glass layer 24 is laminated abovethe conductive layer 22 by using an OCA 23 to construct the touch screenpanel 20.

Although not shown, the conductive layer 22 may alternatively be coatedon a lower surface of the window glass layer 24, which is laminatedabove the ITO sensor glass layer 21 by using the OCA 23.

According to an exemplary embodiment of the present invention, a controlunit 27 and an FPC 28 are mounted on one of the surface of the ITOsensor glass layer 21 and the surface of the window glass layer 24 onwhich the conductive layer 22 is coated. The control unit 27 and the FPC28 may be mounted on one of the surface of the ITO sensor glass layer 21and the surface of the window glass layer 24 by using TAB. Preferably,the control unit 27 may be implemented with a TCP on which a pluralityof ICs is mounted. The TCP may be mounted above the surface of the ITOsensor glass layer 21 or below the surface of the window glass layer 24in an electrical bonding manner. In this case, an ACF 26 is used as anadhesive member for providing bonding between electrodes of theconductive layer 22.

The FPC 28 protrudes with a specific length by using the ACF 26 and isused for electrical connection to a circuit board of the device. Aconnection member 181 is formed at one end portion of the FPC 28 toprovide electrical connection with the device.

As is shown in FIG. 4, an oxidation protection coating layer is notnecessary since a bonding portion of the control unit 27 and the FPC 28can be laminated such that the bonding portion is covered by an OCA 23and a window glass layer 24.

The aforementioned constitutional elements perform the same functioneven if they are indicated by different numeral references. Whilecertain elements of touch screen panel 20 have been shown in FIG. 4 anddescribed herein, the touch screen panel 20 is not limited thereto andmay include other elements that are not shown in FIG. 4 or describedherein for conciseness in explanation.

FIG. 5 is a cross-sectional view illustrating a structure of a touchscreen panel according to another exemplary embodiment of the presentinvention.

Referring to FIG. 5, a touch screen panel 30 includes a conductive layer32 that is laminated below a window glass layer 34. The conductive layer32 is preferably made of a transparent conductive material including oneof ITO, IZO, etc. An electrode pattern is formed on the conductive layer32, and electrical connection may be possible through a silver pasteelectrode portion (not shown) in one or more ends of the conductivelayer 32. In this case, an additional ITO film layer is unnecessary. Inaddition, in this case, a control unit 37 and an FPC 38 may be mountedon the lower surface of the window glass layer 34. The control unit 37and the FPC 38 may be mounted on the lower surface of the window glasslayer 34 by using TAB. Preferably, the control unit 37 may beimplemented with a TCP on which a plurality of ICs is mounted. The TCPmay be mounted on the lower surface of the window glass layer 34 in anelectrical bonding manner. In this case, an ACF 36 is used as anadhesive member for providing bonding between electrodes of theconductive layer 32. The FPC 38 protrudes with a specific length byusing the ACF 36 and is used for electrical connection to a circuitboard of the device. A connection member 381 is formed at one endportion of the FPC 38 to provide electrical connection with the device.In addition, an oxidation protection coating layer 35 may be laminatedon an exposed lower portion of the conductive layer 32 to protect theconductive layer 32.

The aforementioned constitutional elements perform the same functioneven if they are indicated by different numeral references. Whilecertain elements of touch screen panel 30 have been shown in FIG. 5 anddescribed herein, the touch screen panel 30 is not limited thereto andmay include other elements that are not shown in FIG. 5 or describedherein for conciseness in explanation.

According to exemplary embodiments of the present invention, a touchscreen panel has a control unit mounted on a relatively solid glasslayer of the touch screen panel. Therefore, touch sensitivity isimproved by preventing a contact failure of the control unit due tobending or the like, thereby contributing to the resiliency and thereliability of a device.

While the present invention has been shown and described with referenceto certain exemplary embodiments thereof, it will be understood by thoseskilled in the art that various changes in form and details may be madetherein without departing from the spirit and scope of the invention asdefined by the appended claims and their equivalents.

What is claimed is:
 1. A touch screen panel comprising: an Indium TinOxide (ITO) sensor glass layer; a window glass layer mounted above theITO sensor glass layer by means of an Optical Clear Adhesive (OCA); aconductive layer disposed between the window glass layer and the ITOsensor glass layer, the conductive layer including an electrode patternfor sensing a touch; a touch screen control unit mounted on one of thewindow glass layer and the ITO sensor glass layer on which theconductive layer is mounted; and a Flexible Printed Circuit (FPC) bondedto an end portion of the conductive layer and protruding from the endportion of the conductive layer, the FPC including a connection memberon an end portion thereof electrically connected to a circuit board,wherein the touch screen control unit is a control unit for controllinga touch screen, and wherein the touch screen control unit is disposed ona portion in which the window glass layer and the ITO sensor glass layerdo not overlap.
 2. The touch screen panel of claim 1, wherein the touchscreen control unit is implemented with a Tape Carrier Package (TCP)that includes a plurality of integrated circuits.
 3. The touch screenpanel of claim 2, wherein the TCP is bonded with an AnisotropicConductive Film (ACF) by using Tape Automated Bonding (TAB).
 4. Thetouch screen panel of claim 2, wherein the Flexible Printed Circuit(FPC) is bonded to the end portion of the conductive layer by using anAnisotropic Conductive Film (ACF).
 5. The touch screen panel of claim 2,wherein the touch screen control unit is mounted on the ITO sensor glasslayer on which the conductive layer is coated.
 6. The touch screen panelof claim 5, wherein the touch screen control unit is mounted on aportion of the ITO sensor glass layer on which the OCA does not overlapwith the window glass layer.
 7. The touch screen panel of claim 6,wherein an oxidation protection coating layer is coated on an exposedportion of the conductive layer.
 8. The touch screen panel of claim 5,wherein the touch screen control unit is mounted on a portion of the ITOsensor glass layer surface on which the OCA overlaps with the windowglass layer.
 9. The touch screen panel of claim 2, wherein the touchscreen control unit is mounted on the window glass layer surface onwhich the conductive layer is coated.
 10. The touch screen panel ofclaim 9, wherein an oxidation protection coating layer is coated on anexposed portion of the conductive layer.
 11. The touch screen panel ofclaim 1, wherein the conductive layer is comprised of a transparentconductive material.